Process for regeneration of contact masses

Claim 1

THE METHOD OF HYDROFINING HYDROCARBON FRACTIONS WHICH COMPRISES CHARGING THE HYDROCARBONS AND HYDROGEN TO A MULTI-BED REACTOR CHARGED WITH A FIXED BED OF HYDROFINING CATALYSTS MAINTAINED UNDER ACTIVE HYDROFINING CONDITIONS, MAINTAINING THE CHARGE STOCK IN CONTACT WITH THE CATALYST UNTIL THE DESIRED CONVERSION IS EFFECTED, CONTINUING THE HYDROFINING REACTION UNTIL THE ACTIVITY OF THE CATALYST IS SUBSTANTIALLY REDUCES BY THE ACCUMULATION OF CARBONACEOUS DEPOSITS THEREON, DISCONTINUING THE SUPPLY OF HYDROCARBONS TO SAID REACTION ZONE, INTRODUCING AN OXYGEN-CONTAINING REGENERATION GAS TO AN INTERMEDIATE PORTION OF SAID CATALYST BED, PASSING OXYGEN-CONTAINING REGENERATION GAS UPFLOW THROUGH THE UPPER PORTION OF THE CATALYST BED CARRYING A PORTION OF THE SCALE THAT ACCUMULATES AT THE TOP OF THE BED AS WELL AS HEAT AND PRODUCTS FORMED IN THE OXIDATION OF SUCH SCALE RAPIDLY OVERHEAD AND AWAY FROM THE BODY OF THE CATALYST AND SIMULTANEOUSLY PASSING OXYGEN-CONTAINING REGENERATION GAS DOWNWARDLY THROUGH THE LOWER PORTION OF THE CATALYST BED WHEREBY THE TIME THAT THE AVERAGE CATALYST PARTICLE SUBJECTED TO THE DETERIORATING ACTION OF THE HOT GASES FROM THE BURNING ZONE IS MATERIALLY REDUCED.